Evaluation of the analgesic and anti-inflammatory activities of Annona senegalensis Pers. (Annonaceae) leaves aqueous extract in rats and mice

Annona Senegalensis Pers. (Annonaceae) is a medicinal plant used to treat many pathologies, including inflammatory diseases and pain. The aim of this study was to investigate the analgesic and anti-inflammatory properties of Annona Senegalensis leaves aqueous extract in mice and rats. The analgesic activity was evaluated using the acetic acid (1%) induced writhing test and formalin (1%) test. The anti-inflammatory activity was performed using the carrageenan and the dextran induced hind paw oedema in rats. The extract induced a significant (p<0.05) and dose-dependent decrease in abdominal contortions compared with control mice. The maximum inhibition was 63.36% at the dose of 200 mg/kg body weight. Only the late phase of formalin induced nociception was significantly inhibited by the extract with a maximum inhibition value of 56.96% at the dose of 200 mg/kg body weight. In the anti-inflammatory investigation, the aqueous extract of the leaves of Annona Senegalensis produced a significant (p<0.05) and dose-dependent decrease in edema induced by carrageenan and dextran. The maximum inhibition was 57.14% obtained at the fifth hour at the dose of 200mg/kg for the carrageenan test.  For the dextran test, the maximum inhibition was 59.80% obtained at the second hour at the dose of 200 mg/kg body weight.  Our results show that Annona Senegalensis has peripheral analgesic and anti-inflammatory properties. It could therefore be an advantage in alternative medicine. Keywords: Analgesic, Anti-inflammatory, Annona Senegalensis, Rats, Mice